Play Station II - need solution?

I purchased PS II (slim type - new version) about 2/3 years back in Singapore. On return to India I used it for couple of months almost all DVDs played well. But subsequently I had problems running them. When I play them, system configuration would open instead game to start. Sometimes, the screen would say insert PS II format CD (Though I tried everywhere I have never come across such thing as PS II Format CD). Some of the DVDs would work and play after restarting console 10-15 times. But then picture gets blurred and gets stuck and if you restart it would not play again. Some time back I purchased CDS from one reputed store and those DVDS too could not be not played. After talking to the manufacturer he told me that there is something like transmission system. In India we have PAL and in Singapore its something else. So the Play station bought in Singapore is not compatible to be used with DVDs available in India. I checked on DVDs some were PAL and some were NTSC. But both types of DVDs could be played on the console. I do not know what to do. I hope some of you guys might help me out with the solution.